HARRISBURG, Pa. -- Civil rights lawyers filed the first known legal challenge Tuesday on behalf of 23 men, women and children seeking to overturn a 17-year-old state law effectively banning same-sex marriage in Pennsylvania, the only northeastern state that doesn't allow it or civil unions.

The lawsuit, filed in federal court in Harrisburg, also asks a federal judge to prevent state officials from stopping gay couples from getting married. It names Gov. Tom Corbett, Attorney General Kathleen Kane and three other officials.

The plaintiffs are a widow, 10 couples and one of the couples' two teenage daughters. They include four couples who were legally married in other states but whose marriages go unrecognized by Pennsylvania.

Same-sex marriage is legal, or soon will be, in 13 states. The lawsuit seeks to legalize it in Pennsylvania and to force the state to recognize the marriages of same-sex couples who wed in other jurisdictions.

Dr. Nan Van Den Bergh, clinical professor at Florida International University's School of Social Work, shares this video from the The National Institutes of Health.

From the website:

The National Institutes of Health (NIH) is committed to improving the health of all Americans, including lesbian, gay, bisexual, transgender and intersex (LGBTI) Americans, through basic, translational, and clinical research. At this Listening Session, we will begin seeking community input to determine the highest priority research areas in LGBTI health.

She and her former partner married first in San Francisco in 2004, when then-Mayor Gavin Newsom allowed same-sex couples to tie the knot; then in a ceremony that took place before family and friends; and finally in a civil ceremony in October 2008, not long before Proposition 8 banned gay marriage in California.

Two years ago, Ikemoto got divorced.

"When San Francisco allowed us to get a marriage license, it was kind of 'We need to make a stand,' " said Ikemoto, 42, who lives in Sacramento and works for the state.

And the couple kept making a stand, she said, even as the relationship faded.

"Maybe if we'd always been considered equal partners by the state," she said, "I wouldn't have been so eager to rush into it."

Sometimes, marriages just don't work out. The flip side of gay marriage is, of course, gay divorce. With the legal resumption last week of same-sex marriage in California, the state's family law attorneys are gearing up for what happens when some of those marriages fail.